Obesity has been linked to increased risk for cancer. Few programs have been developed and tested for obesity prevention. This study will provide feasibility, and preliminary outcome data, on a highly innovative nutrition intervention designed to prevent obesity as a means of reducing cancer risk in children. The intervention is designed for delivery to families through a managed care setting, Kaiser Permanente of Southern California (KPSC). Computer tailored print newsletters and Motivational Interviewing techniques will be used in the intervention. This project will be completed in two phases. In phase I (Months 1-11), the OPT for Health intervention components will be developed and the measurement protocols will be adapted. The intervention components have been designed using established theories in health behavior, research on the predictors of diet in children, and knowledge gleaned from prior nutrition-related tailored literature. A Motivational Interviewing protocol will be developed for delivery to the parents. In phase II (Months 12-24), the OPT for Health intervention will be evaluated using a randomized experimental design in which families (N=80) will be recruited from the KPSC membership database, matched on single or dual parent household status and number of children living in the home, and randomly assigned to the OPT for Health intervention condition or a usual care control condition. Families in the control condition will receive usual care in the Kaiser system, which includes notification and access to classes on diet and weight control. Measures of diet, psychosocial variables, fruit and vegetable availability, and height and weight (BMI) will be completed on the target children (10 to 11 year olds) and one parent in each family. Assessments will occur at clinic sites of KPSC, a major health maintenance organization in the Los Angeles area. The OPT for Health pilot intervention will include one computer tailored nutrition newsletter for parents and one for target children, one family activity for both parents and children with instructions included as part of the tailored newsletters, and one Motivational Interviewing telephone call for parents. Extensive process evaluation will be completed. Recruitment, intervention and measurement will occur over 11 months using a rolling recruitment and intervention strategy. Four families will be recruited weekly with the baseline assessment completed shortly after recruitment. Randomization to conditions will then occur and the intervention will be delivered over a ten week period. The posttest will be completed one month after the intervention is completed and will provide outcome measures and measures of potential mediators for observed changes in diet and BMI. If feasible, the intervention will be expanded to include dietary fat and physical activity and will be rigorously tested using R01 funding from NIH. This project satisfies two criteria for R21 funding: 1) developing prevention programs for managed care settings, and 2) developing dietary interventions. It also satisfies the general objective of funding creative, innovative feasibility studies for cancer prevention and control. [unreadable] [unreadable]